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  • The analysis of the fair data of a solar energy power plant with SPSS
    60-63
    Views:
    130

    The use of fossil energy sources greatly damages the environment. Moreover, the quantity of these energy sources is limited. Therefore, it is important to increase the share of renewable energy sources (solar, wind, water and biomass) in energy generation.
    Huge amounts of energy (1100-1300 kWh/m2 per year) arrive at the earth from the sun, and are utilized in passive and active ways. One of the active applications is photovoltaic current production, in the course of which electricity is produced directly with PV – panels. This can be fed into a grid. At the University of Debrecen is a solar energy power plant from September 2005 in operation. The electricity performance of the incorporated PV-panels (Kyocera, Dunasolar, and Siemens) are 8.64 kW. The are of PV – panels is 110 square meter. With the aid of the data storage, the tension, current, temperature of the PV-panels, global radiation, air temperature, wind speed, wind direction and the achievement is measured by the ac network.
    The effect of the shading on the performance of the PV – panels and the solar energy power plant is examined. The analysis and the graphic representation of the experiment results are carried out with SPSS per grief. We produced per grief.

  • Nutritive value of Timothy (Phleum pratense L.) during primary growth in 2005
    61-67
    Views:
    141

    In this paper we analysed the change of the chemical composition and nutritive value of Timothy observed during the spring of 2005. The nutritive value of Timothy was observed between the end of April and the beginning of June relating to the following parameters: crude protein, crude fibre, crude fat, ash, N-free extract, net-energy growth, net-energy lactation, net-energy maintenance, Metabolizable Protein Energy dependent, Metabolizable Protein N-dependent. We also analysed whether a relationship between the environmental factors that affect the
    growing period of grasses and the chemical composition can be detected or not. While testing for correlation, the number of days from 1st January, the amount of heat accumulation, solar radiation and rainfall were considered as independent coefficients.
    For the estimation of weather conditions we calculated the climate index. The observed year can be described as a year with a rainfall above the average and abundant solar radiation. A correlation can be detected between the change of parameters of nutritive value and the quality of the current year. In 2005 the result of the analysis of nutritive value was showed a significance difference with respect to each chemical composition at the rate of P<0.001 depending on the time when the samples were taken.
    According to the outlined data it can be stated that the change of the value of crude protein and ash show decreasing tendency agreeing the research literature. In parallel with the change of nutritive value, the amount of crude fibre and N-free extract increased. However, the value of Net-Energy maintenance showed an alteration only in the first half of the observed period. The same alteration tendency can be detected in the Net-Energy growth and the Net-Energy lactation. 

  • The use of renewable resources is an opportunity and an obligation
    13-17
    Views:
    115

    The renewable energy sources could be used in energy production, while no or only very slightly emit harmful substances to the environment. The solar, wind, hydropower, biomass and heat rational utilization of land contributes to greenhouse gas emissions.
    Renewable energy sources also reduces the dependence on fossil fuels, thus contributing to increase security of supply. The creation of local jobs to strengthen the area's population retaining ability.

  • The Presentation of Debrecen University’s Solar Energy Power Plant
    259-263
    Views:
    97

    Energy plays an important role in everyday life and in the economy. The use of fossil energy sources greatly damages the environment. Besides this, the quantity of these energy sources is limited. Therefore, it is important to increase the share of renewable energy sources (solar, wind, water, biomass) in energy generation. Huge amounts of energy (1150-1300 kWh/m2) arrive at the earth from the sun, which utilized in passive and active ways. One of the active applications is photovoltaic current production, in the course of which electricity is produced directly with PV-Panels. This can be fed into the grid.

  • Opportunities of renewable energy use in Hajdú-Bihar and Szabolcs-Szatmár-Bereg counties
    143-146
    Views:
    139

    Today it's an important role of the renewable energy resources, improving energy efficiency, thereby contributing to sustainable, ecofriendly use of local energy resources. Globally intensify the requirements and considerations related to environmental conservation. In this light, the main objective of the Hungarian energy concept is to maintain long-term security of supply, the economy and the environment occurring contradictions. So there is a need for systems that, in compliance with EU environmental directives, acceptable cost level will ensure the desired and expected security of supply. In the study, three companies and other technical parameters of these are examined. For each undertaking, different results were observed. For two undertakings, we are talking about realized investments, in one case a prognosis was examined. All three companies contributed to the requirement of renewable energy sources reaching 13% in Hungary by 2020.

  • Operational experiences of a geothermal heat pump system
    115-118
    Views:
    151

    Energy consumption nearly 40% operation translates of the buildings in Hungary. In the last 5–8 years we can see a breakthrough in the field of low energy buildings, increasing the demand for buildings 'energy efficient', and realized several successful investments in our country. Nowadays thanks to the application system the number of public buildings increased environmental energy recovery system has been growing such as solar power, heat pumps.

  • Evaluation of water balance in apple and pear trees
    193-198
    Views:
    147

    A significant proportion of the aboveground green and dry weight of the plant constitutes the foliage. The canopy is an important factor
    of plant growth. On one hand the canopy absorbs the solar energy, which is necessary for the photosynthesis, on the other hand accumulates
    the absorbed nutrients by the roots, and the most of the water-loss happens through the foliages. The determination of the full canopy is not
    an easy target. In our research we developed a measurement method to determine the leaf area. With the parameters of the examined tree
    (leaf length and maximum width) and the data of ADC AM 100 leaf area scanner we determined the k-value, with which we can easily and
    fast evaluate the leaf surface. Furthermore we defined from the water balance of compensation lysimeters the cumulative transpiration of
    fruit trees and the efficiency of water use of trees.

  • Water managed properties of apple and pear trees based on lysimeters
    129-132
    Views:
    176

    A significant proportion of the aboveground green and dry weight of the plant is constituted by foliage. The canopy is an important factor of plant growth. On the one hand, the canopy absorbs solar energy, which is necessary for photosynthesis; on the other hand, it accumulates the nutrients absorbed by the roots, and most of the water-loss occurs through the foliage. The determination of the full canopy is not an easy target. In our research, we developed a measurement method to determine the leaf area. With the parameters of the examined tree (leaf length and maximum width) and the data of the ADC AM 100 leaf area scanner, we determined the k-value, with which we can easily and fast evaluate the leaf surface. Furthermore, we defined from the water balance of compensation lysimeters the cumulative transpiration of fruit trees and the efficiency of water use of trees. From the examined trees were made a 3D depiction, which show the shape, branching and the location of trees.

  • Assessment of Environmental Susceptibility/Vulnerability of Soils
    62-74
    Views:
    100

    Soils represent a considerable part of the natural resources of Hungary. Consequently, rational land use and proper soil management – to guarantee normal soil functions – are important elements of sustainable (agricultural) development, having special importance both in the national economy and in environment protection.
    The main soil functions in the biosphere are as follows: conditionally renewable natural resource; reactor, transformer and integrator of the combined influences of other natural resources (solar radiation, atmosphere, surface and subsurface waters, biological resources), place of „sphere-interactions”; medium for biomass production, primary food-source of the biosphere; storage of heat, water and plant nutrients; natural filter and detoxication system, which may prevent the deeper geological formations and the subsurface waters from various pollutants; high capacity buffer medium, which may prevent or moderate the unfavourable consequences of various environmental stresses; significant gene-reservoir, an important element of biodiversity.
    Society utilizes these functions in different ways (rate, method, efficiency) throughout history, depending on the given natural conditions and socio-economic circumstances. In many cases the character of the particular functions was not properly taken into consideration during the utilization of soil resources, and the misguided management resulted in their over-exploitation, decreasing efficiency of one or more soil functions, and – over a certain limit – serious environmental deterioration.
    Soil resources are threatened by the following environmental stresses:
    – soil degradation processes;
    – extreme moisture regime;
    – nutrient stresses (deficiency or toxicity);
    – environmental pollution.
    Environmental stresses caused by natural factors or human activities represent an increasing ecological threat to the biosphere, as well as a socio-economic risk for sustainable development, including rational land use and soil management.
    The stresses are caused by the integrated impacts of various soil properties, which are the results of soil processes (mass and energy regimes, abiotic and biotic transport and transformation and their interactions) under the combined influences of soil forming factors. Consequently, the control of soil processes is a great challenge and the main task of soil science and soil management in sustainable development.
    The efficient control of these processes necessitates the following consecutive steps:
    • registration of facts and consequences (information on land and soil characteristics, land use, cropping pattern, applied agrotechnics, yields, with their spatial and temporal variability);
    • evaluation of potential reasons (definition and quantification of soil processes, analysis of influencing factors and their mechanisms);
    • assessment of the theoretical, real, rational and economic possibilities for the control of soil processes (including their risk-assessment and impact analysis);
    • elaboration of efficient technologies for the „best” control alternatives (best management practice).
    Scientifically based planning and implementation of sustainable land use and rational soil management to ensure desirable soil functions, without any undesirable environmental side-effects, require adequate soil information. In the last years such data were organized into a computer-based GIS soil database in Hungary, giving opportunities for the quantification, analysis, modelling and forecasting of the studied environmental stresses and for the efficient and scientifically based prevention, elimination or reduction of environmental stresses and their unfavourable ecological and economical consequences.
    Special attention was paid to the assessment of various soil degradation processes, as: (1) soil erosion by water or wind; (2) soil acidification; (3) salinization and/or alkalization; (4) physical degradation (structure destruction, compaction); (5) extreme moisture regime: drought sensitivity and waterlogging hazard; (6) biological degradation; (7) unfavourable changes in the plant nutrient regime; (8) decrease of natural buffering capacity, (9) soil (and water) pollution.
    The actions against undesirable environmental stresses and their unfavourable consequences are important elements of sustainable, efficient, economically viable, socially acceptable and environmentally sound crop production and agricultural development. These are joint tasks of the state, decision makers on various levels, the land owners, the land users and – to a certain extent – of each member of the society.

  • Energy efficiency in Hungary and abroad
    147-150
    Views:
    131

    Nowadays decentralized energy supply and the energy security are becoming more involved. We should increase the share of renewable in the energy mix, addition to improve the energy efficiency. Hungary is not an abundance of fossil resources it is particularly important in the materials and energy-saving technologies, waste recovery, increasing the share of environmental energy. Our country has outstanding opportunities many areas for example, solar energy, geothermal energy, so we need to devote more attention to renewables in the future.

  • Calculating possibility of the leaf area index of apple and pear trees
    229-233
    Views:
    164

    A significant proportion of the aboveground green and dry weight of the plant constitutes the foliage. The canopy is an important factor of plant growth. On one hand the canopy absorbs the solar energy, which is necessary for the photosynthesis, on the other hand accumulates the absorbed nutrients by the roots, and the most of the water-loss happens through the foliages. The determination of the full canopy is not an easy target. In our research we developed a measurement method to determine the leaf area. With the parameters of the examined tree (leaf length and maximum width) and the data of ADC AM 100 leaf area scanner we determined the k-value, with which we can easily and fast evaluate the leaf surface.

  • Application fields of wood as a renewable energy source in Europe
    31-35
    Views:
    144

    Fuelwood, and wood wastes provide almost half of the renewable energy production of the European Union. Enhancing the use of wood in renewable energy production has more constraint than wind- or solar energy. Forests in the EU member states are sustainably used, they are increasing both in terms of area, and growing stocks. There are possibilities to enhance the fallings and use more fuelwood. Short rotation coppices could fulfill the long term demand for fuelwood; because these plantations surpass the dendromass yield of forests.

  • The effect of sunburn damage on the fruit quality parameters of apple (Malus domestica cv. Idared)
    55-64
    Views:
    178

    In the present study the authors investigated the effect of sunburn injury on fruit quality parameters (cover colour, depth of tissue damage, fruit flesh firmness, dry matter content) of apple.
    The symptoms of sunburn injury appeared as concentric rings, differing in colour from each other and the cover colour. This can be connected with the ratio of the injury. The authors observed the following colours on the fruit surface (from the epicentre of spots on the surface of the fruit) dark brown (strongly damaged), light brown (moderately damaged), pale red transition (weakly damaged), red surface cover colour (not damaged).
    Sunburn of apple fruits is a surface injury caused by solar radiation, heat and low relative humidity. In the initial phase, a light corky layer, golden or bronze discolouration and injuries of the epidermal tissue appear on the surface exposed to radiation. Thus, it detracts from the fruit’s appearance, but in most of the cases it would not cause serious damages in the epidermal tissue. The depth of tissue damage is not considerable, its values are between 1.5-2.0 mm in general. It is commonly known, that tissue structure of the apple fruit is not homogeneous. Accordingly, the degree of injury shows some differences under the different parts of the fruit surface.
    On the basis of the flesh firmness studies, it can be stated that the flesh firmness of the damaged parts increases due to the sunburn effect. This is due to the fact that the damaged plant cells die, the water content of the tissue decreases and it hardens. However, due to this reduction in the water content the dry matter content will increase.

  • Energy use – in terms of efficiency
    61-66
    Views:
    169

    In the recent decades it has become apparent that the human race can lead to a polluting and energy- wasting lifestyle and the depletion of natural resources and an ecological disaster as well.

    Energy efficiency is the realization of the chance to see a wider use of renewable energy. Renewable energy sources can be found in large quantities in Europe. A proper exploitation of these would be important because of the "traditional" energy sources’s sate is very critical in many ways.

    The utilization of renewable energy sources depends on many factors. The local natural conditions significantly determine each country's different renewable energy potentials. I find to be important the natural conditions, such as, solar radiation intensity , the number of sunny days per year, the wind conditions , the volume and their energy characteristics of the geothermal power resources , land features , soil and rock quality, the supply of fossil fuels or the nuclear possibilities of energy production. The economic environment is also a major influencing factor for the utilization of renewables. The conditions of price of fossil fuels (natural gas, oil and coal), the price of nuclear fuel production and other energy costs significantly influence the demand for renewables, as well as the level of subsidy and government tax policy. In addition, the international and national programs, objectives, strategies, subsidies and regulatory measures as well as technological factors can have a significant impact.

    In my paper I point out the opportunities of renewable energy should be given to live. Nowadays the positive effects of their use is undisputed. In addition to the environmentally friendly produced energy, we should strive for energy conservation and energy efficiency as well. These expectations appear in practice, which can be directly perceived by citizens, in fact we should live accordingly. Furthermore, the environmentally relevant regulations of living conditions should appear as environmental demands.

  • Daily behaviour of Hungarian Grey Cattle under range grazing conditions
    45-48
    Views:
    198

    Cattle behaviour on rangeland depends on external factors, such as grass allowance and quality, temperature, net solar radiation, distance from water-source, wind speed and direction, air pressure changes and the applied breeding technology. Our research is based on previous empirical observations and modern methods to analyze the behaviour of the Hungarian Grey Cattle. Today it is crucial to use cost-effective solutions in modern beef cattle farming therefore we introduce a cost-efficient method to study and follow cattle herds. We are studying relation between traveled daily distance and air pressure. The various weather fronts influence behavioural characteristics and traveled daily distance. According to our hypothesis, the pressure-change and the wind direction has significant effect on cattle activity on pasture. As the different air masses alter the barometric conditions and unbalance the neuroendocrine system, indirectly cause relaxed or agitated behaviour

  • Renewable energy resources in the EU (Policy scenario)
    143-146
    Views:
    124

    The use of renewable energies has a long past, even though its share of the total energy use is rather low in European terms. However, the tendencies are definitely favourable which is further strengthened by the dedication of the European Union to sustainable development and combat against climate change. The European Union is on the right track in achieving its goal which is to be able to cover 20% its energy need from renewable energy resources by 2020. The increased use of wind, solar, water, tidal, geothermal and biomass energy will reduce the energy import dependence of the European Union and it will stimulate innovation.

  • The Effect of Sunburn on Fruit Quality of cv. Idared Apple
    23-31
    Views:
    114

    The aim of this study is to investigate the effect of sunburn injury on fruit quality parameters (colour-coverage, depth of affected tissue, fruit flesh firmness, soluble solids content) of apple.
    The symptoms of sunburn injury appeared in concentric ring shape, differed from each other and surface colour-coverage. This can be due to the ratio of the injury. The authors observed the following colours on the fruit surface (from the epicentre of the blotch on the transversal diameter of the fruit) dark brown (strongly affected), light brown (moderately affected), pale red transition (poorly affected), red surface colour-coverage (not affected).
    Sunburn of apple fruits is a surface injury caused by solar radiation, heat and low air relative humidity that in the initial phase results in a light corky layer, golden or bronze discolouration, and injuries to the epidermal tissue, in the surface exposed to radiation. Thus it detracts from its appearance, but in most cases, it would not cause serious damage to the epidermal tissue. The depth of affected tissue is not considerable, its values are between 1.5-2.0 mm generally. It is commonly known that the tissue structure of apple fruit is not homogeneous. Accordingly, the degree of injury shows some differences under the different parts of the fruit surface.
    On the basis of flesh firmness research, the authors established that the measure of flesh firmness of the affected part of apple fruit increases with the effect of sunburn. The consequence of this is the suffered plant cells will die, the water content of this tissue decreases and the fruit gets harder. This water-loss caused the increase of soluble solids content.